The invention relates to a guide chain for running energy lines between a stationary connection and a movable connection with movable chain links, which define each a channel section extending in the direction of the energy line guide chain.
GB 1 585 656 A1 discloses a guide chain for running lines between a stationary connection and a movable connection. The energy line guide chain is formed by pivotally connected, metallic chain links. The chain links comprise spaced-apart side walls, which are stamped from a sheet of metal and bent into shape accordingly. The spaced-apart side walls of each chain link are interconnected by a connecting plate. The connection occurs by welding, so that the chain links form a welded structure.
For a pivotal connection of adjacent chain links, the side walls comprise a circular aperture in their one end region. In the opposite end region of each side wall, an elongate slot is formed. The apertures of the one chain link are positioned with the elongate slots of the adjacent chain link such that a rivet can be passed through the elongate slot and the aperture. The rivet has a widened head with a cross section greater than the cross section of the aperture and elongate slot, respectively. To secure the rivet, a circlip is provided, which is arranged on the rivet.
The provision of the elongate slot is necessitated by the welded structure of the chain links, since elongate slots are capable of compensating manufacturing-related inaccuracies of the welded structure.
The chain links of the energy line guide chain as disclosed in GB 1 585 656 A1 are adapted for pivoting about the rivets, which extend substantially crosswise to the longitudinal direction of the energy line guide chain.
A further embodiment of a conventional energy line guide chain, wherein the chain links are adapted for deflecting about axes extending crosswise to the longitudinal direction of the energy line guide chain, is disclosed in EP 0 154 882 A1. The chain links of this energy line guide chain consist of a plastic. They are formed by link plates, which are made in one piece. At one end, each link plate possesses a central joint bore. At the other end of each link plate, a central joint pin is molded to the opposite side. When the one end of a chain link is connected to the other end of an adjacent chain link, the joint pin will engage the joint bore. This permits forming a chain strand. Two chain strands are interconnected by crosspieces.
EP 0 544 051 A1 discloses an energy line guide chain, which enables an isotropic bending capability in the space, i.e. a capability of bending uniformly in the space.
Such an energy line guide chain is necessary, for example, for a multiaxial handling device, such as, for example, a robot.
This energy line guide chain is formed by an extruded tubing, whose outer circumferential wall is provided with a plurality of circumferential slots arranged in spaced relationship in the longitudinal direction of the energy line guide chain and extending crosswise to the longitudinal direction of the energy line guide chain. These circumferential slots, which extend over the entire circumference of the tubing, are each interrupted by only one flexibly connecting crosspiece or only two flexibly acting crosspieces diametrically opposite to each other at an angular distance of 180xc2x00. The crosspieces of adjacent circumferential slots are offset relative one another by an angle at circumference of 90xc2x00. The width of the circumferential slots and their spacing between one another are dimensioned in accordance with a desired maximum bending radius of the energy line guide chain.
An energy line guide chain of this kind is problematic in that it is necessary to exchange the entire energy line guide chain, when a segment thereof is damaged, since the energy line guide chain consists of an extruded sectional tubing of plastic. This entails an increased expenditure for repair, since it is also necessary to remove from the energy line guide chain being replaced, lines and hoses extending therein, and to insert them into the new energy line guide chain.
The attachment of the energy line guide chain to a stationary connection or a movable connection occurs by chain links, which are joined to a corresponding connector. EP 0 384 153 discloses the design and construction of different end links of the chain. The chain end links comprise side plates, which are interconnected by a bottom plate. The chain end links are jointed to the adjacent chain link of the energy line guide chain. The bottom plate is screwed to a support or base plate such that the chain end link is rigidly connected to the support or base plate. A further development of a chain end link with a strain relief arrangement for an energy line guide chain is also known from Utility Model G 93 13 011. Likewise in the case of this chain end link, a bottom plate is provided, which is connected to a support or base plate.
Based on the foregoing, it is an object of the present invention to design and construct the known guide chain for running energy lines with spatially movable chain links, so that the energy line guide chain is repairable at relatively little cost. It is a further object of the invention to design and construct the energy line guide chain such that it is capable of receiving greater line weights. A yet further object of the invention is to describe a connecting link, which is easy to apply to a connection point, in particular a connecting link, which assists the deflection capability of the energy line guide chain.
The above and other objects and advantages of the invention are achieved by the provision of a guide chain for running energy lines which distinguishes itself in that it is constructed by individual, spatially limited, i.e., three-dimensionally movable chain links. In an extruded energy line guide chain as known from EP 0 554 051, an articulation is possible only, when the extruded sectional tubing exhibits a certain elasticity. As a result, such an energy line guide chain is capable of receiving only relatively low line weights. In the case of an energy line guide chain, as proposed by the present invention, each chain link comprises two opposite link plates extending in spaced relationship in a longitudinal direction of the energy line guide chain. The link plates are interconnected by at least one crosspiece. Each link plate comprises a joint body and a joint receiver, which extend substantially crosswise to the longitudinal direction of the energy line guide chain. The joint body of a link plate engages the joint receiver of an adjacent link plate. The articulated connection as is formed by the joint body and the joint receiver, does not form an integral part of the chain links, as is the case with an extruded sectional tubing of the energy line guide chain. As a result, the joint bodies and joint receivers may be designed and constructed for a greater load capacity. This applies likewise to the link plates and the crosspiece. As a result of releasably joining the chain links by the articulated connections, it will also be possible to repair the energy line guide chain, when one or more chain links have become defective.
In the case of the energy line guide chain as proposed by the invention, a clearance is provided respectively between the partially overlapping link plates of at least two adjacent chain links. Also each joint body comprises an outer surface area and each joint bore comprises an inner surface area. The outer surface area and the inner surface area define diametrically opposite contact areas where the outer and inner areas are in contact, and diametrically opposite gaps where there is a clearance between the areas. The contact areas thus form a pivot axis extending therebetween and which is perpendicular to the longitudinal direction of the energy line guide chain. The pivoting capability of the individual chain links relative to one another is thus achieved only by having the outer and inner surface areas lie against one another. The clearance which is provided between the partially overlapping plates of adjacent chain links allows the energy line guide chain to deflect substantially crosswise to its longitudinal axis.
According to an advantageous development of the energy line guide chain, it is proposed to make the joint body cylindrical. Preferably, the joint receiver has a substantially oval cross section. An oval cross section also means the shape of a race track. The spacing of the substantially parallel extending segments of the race track shape corresponds substantially to the diameter of the joint body, so that the joint body is rotatable about its longitudinal axis. As a result of providing the joint receiver with a substantially oval cross section, there is a play between the joint body and the joint receiver, which enables a deflection about an axis extending substantially perpendicularly to the longitudinal axis of the joint body and to the longitudinal direction of the energy line guide chain.
Instead of making the joint body cylindrical, the joint receiver as such may also have a circular cross section. In this instance, the joint body has a substantially oval cross section. The cross sectional area of the circular joint receiver is greater than the cross sectional area of the joint body. Likewise, this development of the joint connection of two adjacent chain links allows these chain links to deflect in three dimensions.
The link plates and the crosspiece are made of plastic, preferably in one piece. In this instance, the chain link has a substantially U-shaped cross section. The link plates may be designed and constructed with a closing strap or cover, so as to enable access to the channel of the energy line guide chain. This makes it also possible to lay lines in the channel at a later time, or to remove individual lines from the channel. Likewise, it is possible to examine individual lines in the energy line guide chain, without having to pull these out of the energy line guide chain, as is the case with an energy line guide chain disclosed in EP 0 544 051 A1.
A further, advantageous development of the energy line guide chain according to the invention proposes to adapt two adjacent chain links for a pivotal movement relative to each other at an angle of 45xc2x0.
A yet further advantageous development of the energy line guide chain according to the invention proposes to make the joint body from joint body segments separated from another by slots. In particular, the joint body comprises a radially outward directed collar in the region of its free end segment. In such a configuration of the joint body, the latter or its segments are compressed as the joint body passes through the joint receiver, so that upon completion of the passage, the joint body or the joint body segments return to their initial position, and that the collar extends around the edge of the joint receiver. The collar has a certain safety function, since it enables an improved hold of the chain links. To ensure that the collar does not assume an entraining function during an operation of the energy line guide chain, it is proposed to provide a cavity in concentric relationship with a joint receiver, into which the collar extends with a play. Preferably, the cavity is dimensioned such that the collar does not project laterally from the link plate. Should the lateral surface of the link plate slide along an object, the collar would not abrade, since it is arranged inside the link plate. This arrangement also reduces a possible risk of injury by a collar projecting from the link plate.
A further advantageous development of the energy line guide chain according to the invention proposes that the crosspiece comprises a convexly curved portion, which lies in a plane extending substantially crosswise to the link plate. The crosspiece further comprises an opposite portion made to correspond with the convexly curved portion. The chain links of the energy line guide chain are arranged such that the convex portion of the crosspiece of one chain link engages the corresponding opposite portion of the crosspiece of an adjacent chain link.
This configuration of the crosspiece allows to accomplish that adjacent chain links are guided while being pivoted. A guidance of the chain links is accomplished, preferably by forming the convexly curved portion in a free end region of a projection extending in the longitudinal direction of the energy line guide chain. The crosspiece comprises a cutout that merges into the region, with the cutout narrowing from an end face of the crosspiece in the direction of the concave portion. As a result of narrowing the concave portion, it is possible to limit the deflection capability of adjacent chain links. The advantageous further development of the energy line guide chain allows to accomplish likewise that the crosspieces form quasi a cover, which protects the lines laid in the energy line guide chain against external influences. In particular, it is prevented that dirt particles enter the energy line guide chain.
The chain links of the energy line guide-chain are made preferably of a plastic. In particular, it is suggested that the plastic be fiber-glass reinforced. To simplify the manufacture of the individual chain links, a further advantageous development of the energy line guide chain proposes to make at least the convex portion and the concave portion symmetrical with respect to an axis extending substantially parallel to the longitudinal axis of the energy line guide chain.
To receive greater line weights or for greater self-supporting lengths of the energy line guide chain, it is proposed that two adjacent chain links comprise two spaced-apart outer joint axes. In this instance, adjacent links comprise crosspieces, whose overall extension between the joint axes is greater than the spacing of the joint axes. This allows to prestress the energy line guide chain, thereby enabling it to receive greater line weights. The energy line guide chain with a prestress may also have a greater self-supporting length than is the case with an energy line guide chain without a prestress.
For purposes of limiting the angle of traverse of adjacent chain links and, thus, likewise for forming a predetermined radius of curvature, it is proposed that at least two adjacent chain links comprise two spaced-apart, opposite crosspieces, which extend crosswise to the longitudinal direction of the energy line guide chain. In a stretched state of the energy line guide chain, the crosspieces of adjacent chain links, which extend in a common plane, are spaced from each other. In a curved region of the energy line guide chain, these crosspieces adjoin each other.
A yet further, advantageous development of the invention proposes that the energy line guide chain comprises at least one crosspiece, which can be detachably connected with its one end to a link plate. The other end of the crosspiece is advantageously connected to the link plate by means of a film hinge. The link plate, the film hinge, and the crosspiece may be made in one piece.
In particular, it is proposed that in the region of the film hinge, the crosspiece comprises at least one projection, so that in a closed position of the crosspiece, the projection lies on an edge of the link plate. This allows to accomplish that the film hinge is relieved, when the crosspiece has taken its closed position, and a force is exerted on the crosspiece in the direction of a channel section. In this instance, the force is absorbed by the projection, so that the film hinge is held substantially free of stress. A yet further, advantageous development proposes that the crosspiece forms a cover.
To limit the angle of traverse of adjacent link plates about an axis extending substantially crosswise to the longitudinal direction of the energy line guide chain, it is proposed that the link plate comprises at its one end a stop element and at its other end a stop surface, which is made substantially parallel to a center plane of the link plate. This configuration of the link plate accomplishes that during a lateral swing motion of adjacent link plates, the stop and stop surface prevent the chain links or link plates from locking up.
A further inventive concept proposes a guide chain for running energy lines between a stationary and a movable connection, with jointed chain links of plastic. This guide chain comprises at least one connecting link. The connecting link is designed and constructed such that it facilitates joining the connection link to a connection point or to a connection element, which is attached to the connection point. In particular, the connecting link is designed and constructed such that it assists the deflection capability of the energy line guide chain.
The energy line guide chain of the present invention with at least one connecting link distinguishes itself in that the at least one connecting link comprises a base body with at least one receptacle for receiving a connection element mounted to a connection point, and a locking element cooperating with the base body, which is adapted for locking the connection element with a base body.
More concretely, it is proposed to limit the receptacle by a wall, which is molded to the bottom, and made at least in part spring-elastic, and that the wall forms with the connection element a snap connection. This configuration of the connecting link in combination with the connection element, which is mounted to a connection point, facilitates joining the connecting link to the connection element.
A further advantageous development of the energy line guide chain proposes to form the wall by at least two wall segments, which are separated by slots. Preferably, four wall segments form the wall, with two opposite wall segments being made substantially rigid, and the two further opposite wall segments being made substantially spring-elastic. Preferably, the substantially spring-elastic wall segments comprise corresponding recesses or projections, which form a snap connection with a correspondingly constructed connection element. The spacing of the further wall segments may be greater than the inside width of the connection element, so that only the spring-elastic wall segments produce a connection between the connecting link and the connection element.
A yet further, advantageous development of the energy line guide chain proposes to join the locking element to the base body for displacement therewith, so that the locking element impedes at least the deflection capability of the wall in a locking position, and releases it in another position. This advantageous configuration and further development of the energy line guide chain accomplish that the mounting of the connecting link to a connection element can be realized in a very simple manner and with very little force, since only the spring-elastic wall segments must be pushed apart. A locking engagement is realized by the locking element.
To realize an easy and reliable locking engagement, an advantageous development of the energy guide chain proposes to make the locking element substantially U-shaped. In this instance, the free legs of the locking element lie in the locking position at least in part against the wall, in particular against the elastic wall segments, so that the wall segments are prevented from springing apart.
It is proposed that the base body of the connecting link comprises a slide-in opening, in which the locking element is held for displacement. In the locking position, the free legs lie in part against the wall, in particular against the elastic wall segments and the lateral surfaces of the slide-in opening. This ensures that even in the case of relatively high pull-off forces, the locking engagement remains secured, since the side walls of the slide-in opening restrict the free legs of the locking element in their freedom of movement.
To ensure that a locking engagement of the connecting link with the connection element is enabled only, when the connection between the connecting link and the connection element is properly established, a yet further, advantageous development of the energy line guide chain proposes that the locking element comprises a safety flap, which is spaced from the legs and made substantially parallel to same. In this instance, the locking element can be moved to its locking position only, when the connection element releases the safety flap.
To this end, it is proposed in an advantageous manner to provide the base body with a projection, which extends into the plane of movement of the safety flap. The safety flap comprises an opening, which the projection engages in the locking position. The safety flap can then be deflected by the connection element such that same can be brought to the locking position.
To prevent an automatic release of the locking engagement, it is proposed that the projection and the opening are adapted to each other in their shape, so that a movement of the safety flap is prevented.
A yet further, advantageous development of the energy line guide chain proposes that the receptacle extends fully through the base body. In particular, it is proposed to make the receptacle and connection element rotationally symmetric, thereby allowing the connecting link to perform a swing motion.